Fluid-operated power-transmission mechanism.



I 0. KELLOGG. FLUID OPERATED POWER TRANSMISSION MECHANISM.

APPLIOATION FILED MAY 24, 1907.

Pat nted Dec. 2, 1913.

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- INVENTOR chmzwizizu WITNESSES G. S. KELLOGG. FLUID OPERATED POWER TRANSMISSION MECHANISM.

AAAAAAAAAAAAAAAAAAAAAAAAA 7. 1,080,281 Patented Dec. 2,1913.

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FLUID OPERATED POWER TRANSMISSION MECHANISM.

Patented Dec.2,1913.

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A! 2 Y A M D E I G. S. KELLOGG.

FLUID OPERATED POWER TRANSMISSION MECHANISM.

APPLICATION FILED MAY 24, 1907. I 1,080,281 Patented Dec. 2, 1913.

3 B SHEETS-SHEET 4.

WITNESSES i INVENTO/Y aka/files sJaeao y C. S. KELLOGG'. FLUID OPERATED POWER TRANSMISSION MECHANISM.

APPLICATION FILED MAY 24, 1907.

' :Iatented Dec. 2, 1913.

a' SHEETS-SHEET e.

Mv\ "0% W Tu W m 10 m in WITNESSES 0. s. KBLLOGG. PLUI'D OPERATED POWER TRANSMISSION MEOHANISM.

Patented Dec. 2, 191.

APPLIUATION FILED MAY 24, 1907.

8 SHEETS-SHEET 7.

WITNESSES N VE N 70/? 671a 7166' S? lt'ello gg A TTOHNEYS I c. s. KBLLOGG; FLUID OPERATED POWER TRANSMISSION MECHANISM.

APPLICATION FILED MAY 24, 1907.

' Patented Dec.2,1913.

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WITNESSES A TTOHNEYS UNITED STATES PATENT orurcn.

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To all it may concern Be it known that I, CHARLES Snow Kan- LOGG, a citizen of the United-States, residin in Montclair, in the county of Essex an State of New Jersey, have invented a cer-' tain new and useful Fluid-Operated Power-' Transmission Mechanism, of which the foi lowing 1s a specification.

The invention is a fluid operated mecha-- nism designed, primarily, for the. transmission ofpower from one shaft or member to another shaft or member. "Although said mechanism is especiallyintended for use in connectionwith the driving mechanism of automobiles, it .is to beunderstood that it" invention consists of means whereby the almost wholly upon the circulation of a; more or less inelastic fluid, which "fluid is tor ue or torsional ener communicated to the driven part is augmented and:

increased in direct ratio as the speeds of the driving and driven parts. Furthermore, the torque is controllable and variable at will by the simple adjustment of a valve which re'g' ulates the circulation of a fluid. It is to be understood, therefore, that the variable control and thepower transmitted is dependent instantly governed and regulated merely by the adjustment of a suitablevalve mecha-- nism, whereby the speed ratio of the driving and driven shafts are made .to accord with extent, if not wholly, with the employment of mechanical transmission or speed changing gears, and said mechanism obviates the shock, jar and vibration due to the employment of such gears, more especially when the speed is changed to or fromthe high, low

or intermediate speed gears, which changes.

in speed are frequentlyrequired to meet the road conditions in the practical use of auto-' mobiles.

The full power of the engine can be obtained by running it at the speed at which Specification 01 Letters Iatent.

Application filed-Key 24, 1907.. Serial No.375,529.

Patented Dec. 2, 1913.

that power is developed and varying the ratio of speed of driven and driving shafts to meet the road conditions.

Another part of 'the invention consists of means whereby the friction is minimized.

In my apparatus, the inclosing casing is mounted for rotation freely with respect to the driving and the, driven parts, and consequently the friction of .the circulating fluid is materially reduced. 1'

Another, and an important, feature of my invention consists of means whereby the direction of rotation of the driven part may be reversed with relation to the driving part,

and, furthermore, the speed, of such re-- versed driven part, and the power thereof,'is controllable or regulatable with the same facility as when driving ahead, or in the same direction as the driving part. The capability of the transmission mechanism to reverse the driven part, and to increase the torque of the driven part when operating under such reverse conditions, is an especially useful and meritorious feature of the new transmission mechanism when employed in connection with automobiles, for

the reason that in backing the vehicle out dispensable requirement, at times, to be able to utilize the maximum power of the apparatus. As indicated, an especially useful feature of the apparatus is the instantaneous control of the driven part. when reversed, such advantage being secured by a simple adjustment of a valve mechanism for regulating the volume and pressure of the circulating medium.

Another part of my invention is to utilize the fluid transmission as a brake mechanism for the purpose of retarding or arresting the motion of the driven part bybpposing to.

such driven part avariable fluid resistance,

the circulation of which is regulatable at will by adjusting a valve mechanism so as to offer more or less resistance to such driven part, whereby the speed of an automobile when coasting or when descending a steep grade'can be regulated and controlled.

In the use of the apparatus as a brake mechanism, the rotary casing is held stationary by an appropriate form of brake mechanism, whereas the engine is free to run with the power shut off.

Another part of my apparatus consists of means for mechanically coupling the driven and driving parts. fast one to the other,

- whereby the transmission mechanism'when mcapacitated from service by leakage of the flllld, or from other causes, cannot preclude Qpemmr from running the vehicle under spects as though the mechanism were not apart of the automobile. p Although my apparatus, from one standpoint, is a'variable-power fluid-transmission for automobiles and other machinery, the principle of the invention is available in the construction of a differential gear for automobiles. It. is to be understood, therefore, that it is intended to apply such principle to the difl'erential gearing used in connection with a divided driving axle, each member of which has a motor connected with a fluid pump by a closed fluid circulating system adapted to supply the fluid to such'motorfi and thereafter return the fluid back to sai pump. Suitable provision is made for controlling the direction of flow of the fluid in order that the motors maybe propelledjfor-- ward or backward, as circumstancesmeouire,

and, further, provision is made foroperatmg one motor with greater power than the other motor, in order to dislodge one of the vehicle wheels from a rut in the road.

1 85 The foregoing is a brief statement of the therein are to be understood as illustrative 4 only, and not as defining the limits of said invention.

Figure 1 is a vertical longitudinal section through a fluid operated transmission mechanism constructed in'accordance with this invention, the plane of the section being'in- .dicated bythe dotted line 1-1 of Fig. 2. Fig. '2 is a vertical cross section through the v apparatus: on the line 2-2 of Fig. 1 looking in the direction of the arrow, said figure showing one form of rotary pump consistmg of a driving element which operates to force fluid into a plurality of motors, the latter operating the driven element. Figs.

. 3 4, and 5 are detail sectional views on the lines 3--3, 4-4, and 5-5 respectively, of Fig. 9 showing the different construction of a controlling valve which operates to regulate the circulation of a fluid from the pump mechanism to the plurality of motors,.whereby two or more of said motors maybe brought into-service, or the motors may be detail view showing a reversing valve adjusted to an opposite position to that in which said valve is shown in Fig. 6. Fig. 8 8o is a detail cross section illustrating one embodiment of means whereby a normally loose or idle motor member may be made fast with the drivenshaft when it is desired to bring the idle motor into operative relation tosaid shaft for the purpose of increasing the power of the transmission mechanism and consequently secure increased torque on the driven element. Fig. 9 is a. vertical longitudinal section through i the apparatus taken in the lane of the dotted line 9-9 of -Fig. 2 'ng in the direction of the arrow and showing certain parts in elevation. Figs. 10 and 11 are vertical sections taken in planes at right angles one to the 5 other illustrating another embodiment of means adapted to make the idle motor fast with the driven shaftfi said means being operated in one direction or the other accord- ,ing as the motive fluidis pumped in one di- 100 rection or the other. Figs. 12 and 13' are diagrammatic views illustrating the application of my invention to the differential gearing employed in automobiles. Figs. 14 and 15 are-diagrammatic views of the fluid driving mechanism illustrating the course of circulation of the fluid when propelling direct and in reverse. Fig. 16 is a section partly in elevation showing a preferred form of the driving mechanism. Fig. 17 is a detail section on the line 17--17 of Fig.16.

For the purpose of explaining my invention I will describe the same as it is adapted to be used in connection with .the parts of an automobile, but as hereinhefore stated it is to be understood that I do -not limit the invention to use in'this particular art.

A designates the driving element or member and'B the driven element or member, said element or member, A, being in the present instance a shaft adapted to be propelled by a motor or engine, and the element or member, B, a shaft from which power 'is taken for propelling an automobile. As shown, the shafts, A. B, are in the same-horizontal "plane, in alinement one with the other, the adjacent ends of the shafts being separated, but it is not intended to limit the invention to shafts of the particular form in Figs. 1 and 9 for the reason .that'one shaft 1 crating an abutment, E, which cooperates- 1,oso,2s1

may be tubular and arranged to incasea part of the other shaft, as in Fig. 16, 'whereby the two shafts are fitted telescopically to- I gether in order that they may reinforce one another andbc arranged in compact order.

C designates a casing which forms one of the working parts of the apparatus and incloses other working parts of the apparatus.

Said casing fits over or houses the adjacent ,or overlap ing ends of the driving and driven sha ts, A,'B, respectively. This casing is constructed interiorly to provide a number of chambers, one of which forms a chamber for the piston member of a rotary pump, while other chambers receive the rotary'pistons of certain fluid operated motors,

and still other chambers accommodate a valve or valves for, controlling the circulater being a pump chamber for the'fiuidadapted to be forced through the apparatus by the operation of the piston, D, the latter being keyed as at d on the shaft, A, or made fast therewith in a suitable way. The pump chamber, 0, is formed by a part of the easing, C, and the interior divisions or walls, 0, 0 the fatter forming a sub-chamber 0 adapted to contain suitable gearing for opwith the pump piston, D. Said piston is shown in the drawings as consisting of a hollow cylinder with flat ends adapted to serve as a reservoir for the storage of the fluid to be forced by the pump through the casing, C, and into one or more motors, but it will be understood that ,it is not intended to ,limit the invention'to a formv of rotary pump wherein the piston, D, is concentric with the shaft, A, and which necessarily employs a rotatable abutment, E, in connection with said concentric piston, for the reason that I reserve the right to substitute a rotary eccentric piston pump in lieu of the concentric piston pump shown in the present exemplification of the invention. The piston,

D, isprovided with a plurality of radial ports, (Z, for permitting the motive fluid to be drawn or forced by centrifugal energy from the reservoir chamber into the pump chamber, 0. The aforesaid pump chamber, a, in the casing, C, is, furthermore, subdiv'ided into a plurality of (fluid-containing compartments by the empldyment of one or more partitions, e, spaced in said chamber,c, between the side walls, 0, c thereof, as clearly shown in Figs. 1 and 9. The part1- tions 6, are parallel to eachother and the walls, 0, a and they embrace the. piston,D,

said partitions fitting snugly to the annular wall of the divided pump-chamber, c, and said partitions also fitting snugly to the rotatable abutment, E. Said piston, D, is provided with groups of wings or vanes, (Z The wings or vanes of each group extend radially from the piston, and each group operates in one of the sub-compartments of the divided pump chamber, a. In the construction shown in Figs. 1, 2, and 9, the pump chamber, 0,. is divided bytwo partie tions, e, 6, into three sub-compartments, and each group of wings on the piston, D, comprises three vanes, hencethe piston, D, 'shouldbeprovided with three groups of 30 vanes, one group for each sub-compartment of the chamber, 0, each group consisting'of three wings. It is to be understood, however, that the number of sub-compartments in the pump chamber, the number of groups 35 of vanes on'the piston, and the number of vanes in each group, are not material, so that these parts may be modified or changed by the skilled constructor.

According to this invent-ion a suitable 9o pumping mechanism, of one type or other, is operated directly or indirectly from the engine'shaft, the latter running usually at a uniform rate of speed. Said pump forces a fluid from the chamber, 0, of the casing, 0, into and through certain passages which are provided in said casing, C, said passages forming in said casing an element or part which, for convenience and brevity, is termed in this specification a closed fluid circuit. As shown in-Figs. 2, 6, and 9,'the casing, C, is provided with chambers, f, f, which are positioned at opposite sides of abutment, E, and open directly into the respective ends of pump chambers, 0. With these chambers, f, f, communicates one end portion of passages, j, j, see Fig. (hand these passages, j, j, are, on one side of valves, J, L, connected by by-pass, y, see

Figs. 1, 3, and 6, all as will hereinafter'a-ppear. One branch of said fluid circuit, or in other words, one of the passages, such as j in Figs. 6 and 7, establishes communication through chamber, f, in Fig. 6 with the divided pump chamber, .0, and with a motor chamber, or a plurality of motor chambers, a, a, b; said passage or branch j, communicating at one end with the annular divided chamber, 0, on or at one side thereof, and also communicating, at its other end, with the motor chamber or chambers, see Fig. The other branch .of the aforesaid fluid circuit is in the form of a passage, j, see Figs/ 6 and 7, which branch or passage j", is in communication, also, with the divided an-135 nular pump chamber, 0, and with the motor chamber or chambers, a, a, 7). It is to be. noted, first, that one end of the branch or passage, j, connects with thepump chamher, a, on the opposite side thereof from the branchor' passage, j, while the other end of.

man opposite direction to that just de-' the branch or passage, 4', communicates with the motor chamber or chambers, a, a, b, on the opposite side thereof from the branch or passage, j; and, second, that the branches orfpassages, j, j, are in crossing relation to each other'in. the wall of the casing, C, whereby thecrossing-passages or branches intersect in such manner that a single valve, such as J- (Figs. 6 and 7), may be used in controlling thedirection of the fluid, or reversing the direction of flow of the fluid, as may be desired. Under one condition of service, the passage'or branch, j, and the valve, J when adjusted to the position of -Fig. 6, enables the fluid to pass from one side of the pump chamber, a, through the passage, 7", one port, is, of the valve, J, to-

. andinto one or more of the motor chambers,

a, a, b, thence in one direction through said motor chamber or chambers, thence into the other branch or-passage, j, through another port, is, in the valve, J, and thence back to the pump chamber, a, the returno'f the fluid being on'the opposite side of the pump from that side of which the fluid is forced out by the action of-the pump piston. The fluid is thus forced, under velocity .and pressure dependent upon the speed and power of the pump, from a pump chamber to one or more motor chambers, through a' closed circuit which conveys the fluid from, and returns it back to, the pump chamber, and the fluid is thus adapted to act on one or more motors for driving the same during the circulation of the fluid through said motor chamberor chambers. The reversing valve, J, may,

however, be adjusted to change the course or direction of circulation of the fluid, for the purpose of driving the motor or motors scribed, but under such conditions of reverse munication of the drive of the motor or motors, the pump continues to operate in the same direction as before, for the reason that the engine drives the pump constantly in one direction. 'As shown in Figs, 6 and 7, the reversing valve, J, provided, in addition to the per-ts, is, is, with the surface ports, k is, which are so positioned on said valve as to establish comassages, j, j, with each other andthrough t e valve when said valve is adjusted to the position of Fig.7. Assuming thatlthe pump .is operating to'force liquid from the upper part of the pump chamber, 0, in Fig. 6, and the valve, J, is ad- 7 justed to theposition of Fig. 7, the fluidthrough said motor chamber or chambers in an opposite direction to the passage of the fluid, as first described, thence to and through passage, z", into and thou h'thev other surface port, k ,.of the valve,

passage j back to the pump chamber 0. As stated, the fluid leaves, and is" returned to, the pump chamber in the same mannerunder both adjustments of the reversing.

valve, J, but with the valve, J, adjusted .tq the position of Fig. 6, the fluid passes from right to left clockwise through the motor chamber or chambers, 0, a,b so as to-drive the motor or motors clockwise, "while an adjustment of the .valve, J, to the position of Eig. 7, causes the fluid to circulate from.

and 1' :7 I .thence through the remainingpart oi the with the sub-cham ers or compartments of the. ump chamber, 0. The wall, a, is formed witl fa substantially circular opening, e, the inner surface of which provides a seat for the rotatable abutment, E, thellatter being in the plane of the piston, D, and disposed in contact therewith for the purpose of cooperating with said piston in forcing" the fluid to circulate through the apparatus.

As shown in Fig. 9, the abutment, E, passes through the partitions, e,- e, and sa1d abutment cooperates with the peripheral surface of the piston, D, see Figs. 1, 2, and 9. Said abutment is provided at intervals corresponding with the wings, d of the pump piston with recesses or pockets, 0*, the latter being constructed and located to receive .said wings when the latter come opposite to the abutment, whereby clearance spaces are provided in the abutment for the passage ofthe piston wings at each rotation of the piston. It is preferred to rotate the abutment, E, positively, and to attain this result suitable gears, e, e, are-arranged in the compartment, c of the pump, sa1d gear, 0, being made fast with the dr1v1ng shaft,

A, while gear, 6, is secured to the shaft of i the abutment, E, whereby said abutment is rotated by motion transmitted from said a As shown in Figs. 1 and-9,.the casing, C,

shaft, -A.

is divided interiorly by partitions, g, g, to form other chambers, a, b, respectively, the

chamber, a, being of larger capacity than the chamber, b, and said chambersreceiving the parts const1tuting a duplex rotary motor, G, and an idle rotary motor, H, the latter being a reserve motor adapted to be broughtinto operation when it is desired to increase the power or torque exerted by said motorsupon' the-driven element or shaft, B.

' The motor, Gr, operates in the chamber, a,

and it consists of a rotary piston, G, and the rotatable abutment, G The piston, G,

is'provided with suitable wings adapted to --enter suitable clearance pockets in the abutment in the manner described in connection withthe pump andas is well known to those skilled in the art. In this connection it is desired to state, however, that the motor, G,

is of a doubleor duplexconstruction, and

the capacity of said motor is in excess of the capacity of the pump. As shown, the abutment, U2, is driven from the shaft, B, by suitable gears, g 9 The idle or reserve motor, H, consists of a piston, ii, and an abutment, H which are substantially the 29 same in construction as the motor, Gr,.but it is to be noted that although the pistons, G, .ii, of the'motors', G, H, respectively,'are mounted on the driven'shaft, B, said piston, G, is made fast with the shaft, as for ex- 4 ample by a key, 9 whereas the piston, H,

fluid chamber, 71, leading to the motor chambers, a, b,'by the branch or-passage, j, of the fluidcircuit heretofore described, and in like 40 manner the fluid chambers, f, are adapt- 'ed to communicate with each other by the branch orjpassage, 7', said fluid passages, 7',

j, crossing each other .and'forming the aforesaid liq id circuit in one embodiment of the invention. V c

The reversing valve, J shown in Figs. 1, 6, and 7 of the drawings, iscarried'by a shaft, J, arranged. transversely'.-within the casing, G, and mounted in suitablebea'rings' therein, see Fig. 1. Said shaft, J.,'is controllable at will by means of a train of devices adapted to be set into operationleithe'r by the hand orfifoot of the operator, and as shown, said shaft is provided witha gear pinion, j, with which is adapted to intermesh the teeth on a slidable rack bar, J said rack bar extending beyond the casing' and connected'with an operating collar, J It will be'understood that when the *collar'is N-moved in one direction the shaft, J, and the valve, J, are adjusted sothat the valv'e will move to 'theposition shown in Fig. 6,-

whereby the liquid is adapted to circulate from one sideo thepump to the 'otherside of the motor or'motors. The valve, how- 5 ever, may be adjusted to a reverse position, shown in Fig. 7, for-establishing communication between the passages, j, j, and chambers, f, f, and z', 11, in such manner that the liquid maybe forced from the same side of the pump to the opposite side of the motor or motors from that first described, for the purpose of driving'said motor or-motors in an opposite. direction, thus reversing the direction of flow through the motor or motors of the liquid under pressure from the pump, and driving the motor or motors in a backward direction.-

Any suitable kind of reversing valve, J may be employed, but in the drawings I so have shown one'form of-valve provided with two reversely arranged interior ports, la, is,

and with the surface ports, 70 70 The ports, is, k, extend through the valve, and

aredisposed one above the other, or at dif- '85 'ferent distances from the axis of the shafts,

A, B, see Fig. 1. The port, k,.in'the valve is adapted to register with the two parts, 7', j, of one liquid passage, see Fig. 6, where.- as the other port, is, is in a plane to register with the two parts, j, of the other liquid passage between the pump and the mo tor. This construction of the valve provides for the circulation of a column of fluid impelled by the action of a pump to one side of the motor or motors, and for the return of the fluid fromthe motor back to theother side of the pump.- This is true of the valve ineither of its adjusted positions for the reason that the ports, la, 70, direct the circulationof-the fluid in one direction through the motor or motors for the purpose of driv' ing the same forward, whereas the ports, 72?,

k3, vdirect the fluid, when the valve is reversed, through the motor or motors in an opposite direction so-as to drive said motor or motors in a reverse direction.

As the reversing valve, J, is at the intersection of the passages, j, 7", it is important to construct saidvalve to overcome the O leakage of the fluid under pressure.- This result is accomplished, in .the form of valve shownin Fig. 1, by the employment of a hydraulic packing, 7' the latter having a lip which engages the valve seat, the liquid under pressure being admitted. tosaid lip "by ports, j, in a manner well understood.

- It is well known to those skilled-in the art thatthe internal combustion engines,

commonly employed on automobiles; are

driven at all times in onedirection, and when my. transmission mechanism is used between the driving anddriven shafts of an automobile, the shaft, A, is rotated by the engine constantly in one direct-ion.-

I The shaft, B, from which power is trans-: mitted to the motor vehicle or other apparatus, isadapted to be driven in one direc- Q tion or the other b' the action of the fluid by the pump to the duplex motor, G, or it ing valve, J, however the valve is in the position of Fig. 6, the I motor or motors are driven in the same di-,

rection as the pump, and consequently in the same direction as shaft, A, and the engine but whensaid valve, J, is reversed to occupy the position of Fig. 7, the direction offlow of the liquid is reversed through the circuit, and the motor ormotors, so that said motor or motors are driven in an opposite direction to the pump, the shaft, A, and the engine, thereby providing means for moving the vehicle in a backward direction.

In addition to valve J, for controlling the direction of flow of the liquid so as to drive the motor or motors in the same direction as, or in an opposite direction to, the pump, another valve, L, is employed, which valve regulates the flow of fluid from the pump to the motor or motors, G, H. The valve may be adjusted to preclude the liquid from passing to either motor and to open .the b'y-pass, j, so that the liquid will clrculate from oneside of pump, D, to the other side of the pump, or said valve, (L,

may be adjusted to admit the .fluid for may be further adjusted to admit. the liquid simultaneously to'both motor, Gr, and motor, H. One embodiment of said regulating valve is shown in Figs. 3, 4, 5, and

9 of the drawings, the position of said valve being said drawings.

' ":and the described devices for operating rej casing, C, at one side of the rover indicated in dotted lines in. Fig. 2 of Regulating valve, L, is separate from reversing valve, J; it is supported in rotary valve, and means are employed for operating sagd yersing valve, J

' .Cas1ng, C, is provided with" a longitudinal I valve chamber, m, the same being shown in longitudinal section in Fig. 9, in cross sec- 'tionin Fi 3, 4,--,5, and-10 andin dotted Fig.2, said valve chamber, m, be-

er in cross section. This valve chamber, 122-, is at'one side of 'reversingozalve,

J,fone'end portion of the valve cham r be- I ing adapted to communicate with the mp ber, (see Fig. 2'), said valve chamber exchamber through the interposed fluid c amtendm crosswise of motors, G H, whereby the v ve chamber is adapted f or-co1 nm1m1- cation, also, with either orboth motorchambets, 0, 6, preferably on that side'of said chambers a,".b, into which thefluid is delivered by the passages, j and z'.- e

. Valve, L, extends lengthwise of chamber,

3 m, and casing, C,'see' Fig. 9. Said valve is,

at certain parts of its length,'cut away curved faces which d1 SQOtlODS, o,

transversely, as shown in said Fig. 9, and

the valve is thus provided at points intermediate its ends with. a pluralityof members indicated b n,'0, o and 32, said members-being of di erent cross sectional shapes,

' as shown in Figs. 3, 4, 5, and 10; the valve,

L, being otherwise circular in cross section so as to conform to thecross sectional shape of chamber, m, whereby the valve is seated in contact with the walls of said :chamber, m, for the purpose of turningeasilytherein.

Sections, n, 0,0 and of valve, L, provide,

in said Figs. 3, 4,5,.and 10 the area ofthe curved face on section,.p, being. greater than the area ofthe surfaces on the sections, 0, 0

er in area, as shown whereas the area of the surface on thesecg tion, a, exceeds that of either of the sections,

p, 0'' or 0, individually considered. These several sections of valve, 'L, are adapted to control the flow'of liquid into the several chambers asfollows -section, 72,- travels over the port. to motor chamber, 6', so as to establish or shut off communicationbetween chambers, m, i, and 6, see Figs. 5, 9, and 10;

sections, 0, o, cooperate with the ports of motor chambers, a, a, and chamber,z, so as to open or close commumcation from .chambers,

z, m, to motor chambers, a, a, see'Figs. 4 and.

ports lcadin to motor chambers, a, a, b, but

0', and p, of. valve, L, close thesection a 0 said valve opens-bypass 7 so I that liduid acted upon by the pump will flow. from the. outgoing branch'of pas-=- s age, j, into the oing branch of assage,

7, whereby the liquid is free to circ ateout of and back into the pump chamben- Under 4 these conditions, tha -13am exerts no power on the a paratus or on t e driven member,"

and the iquid circulates merely through the pump'chamber. 1 Should itbedesired to fiperaite motor, G,

in the position of Fig. 6), valve, 13, 18 turned on axis a short distance-seas to move sect1ons, o,o', of said valve in a direction to permit 1i uid to circulate through said ma ot er. s n

tor' cham rs, a, a, andwhenvalve, L',:is

turned, its section, 11, closes theb v-pass, sections '0 o beginning t0-o assage for e-birdulationof liqui 11- motor chambers, a, a, just priorfto'jtjhe c using of presby-pass, j, thus .avor fa burstmg; sureincasmg, C. 'Itwill'; understood that with valve, J, adjusted as 6, the

, tions between saidniembers, as will be here} liquid upon leaving chamber, f, passes through valve, J, on itsiway' to the motor chambers and thereafter 'flows through valve, L, on its way back to the pump. To

bring motor, H, as well as motor, G, into service, valve, L, is turned to a further position, whereupon sections, 0, 0, will permit liquid to flow through motor chambers, a, a, as before, and section, p, of the valve opens motor chamber, 6, for the admission of liquid to motor, H, whereby motors,"G, H, are operated simultaneously by the liquid circulated in casing, G, by the action. of the pump. In either of thedescribed positions of valve, L, for controlling motor, G, or motors, G, H, the liquid passes through valve, J, then through the motors, and through valve, L, on its way back tothe pump. From this description it is apparent that valve, L, performs important functions. \Vhen the valve is adjusted to open the chambers of motors, G, H, driven member, B, is propelled at the slowest speed; but owing to the facts that both motors, G, H, are exposed't-o the action of the liquid circulated by the pump and that both motorscoiipcrate with the driven member, the greatest power is applied to the driveninember, thus securing increased torque on the driven member, the same being at times very desirable. By adjusting valve, L, to shut off the" circulation of liquid through the chamber of motor, H, all the liquid is compelled to circulate in motor, G, and thus the speed of motor, G, and the driven element is increased. WVhen' valve, L, is further adjusted-to shut off liquid from both motors and fromthe by-pass, the liquid is lockedor confined in the casing, C, and thus the casing and motors are caused to rotate with the pump and the driving member, whereby the driving member and the driven member are coupled for unitary rotation by the rotatable casing of the liquid transmission. This coupling of the driving and driven members for unitary rotation may be, and preferably is, accomplished by -.direct mechanical connecinafter described:

-' Under some conditions-of service,":ca'sing, C, is free or unrestrained so that it will be rotated in thesame direction as'the pump and the engine shaft. owing to the pressure of the liquid circulated in the casing! As will hereinafter appear, I associate with this rotating part or easing, C, means,'such as'an automatic dog to restrain the casing from rotating ina backward direction, and employ, also, additional means, such as a band brake, for locking or restraining the rotary part or casing, C, from rotation-ineither direction. Withthe casing, O, looked as described, and the pump actin' to "circulate the liquid through the casing, tiie mechanism acts to reverse the motor, although this re sult may be obtained, also, by the reversing valve hereinbefore described.

It is manifest that valve, L, .may be r0- tated more or less for the two-fold urpose of controlling the by-pass, y, and o admitting liquid into motor chambers a, a, or into motor chambers, a, a and I); urther, that said valve, L, may be turned to regulate the volume of liquid adapted to pass from pump, D, into one or both motor chambers, ar, (4

'and b; and, further, that reversing valve,

J, may at any time be operated independently of valve, L, for the purpose of changing the direction of flow of the liquid through motor chambers a, a, I), should it; become necessary or desirable to drive the motor ormotors in a reverse direction to the rotation of the pump.

Suitable means are provided for rotating valve, L, and as shown in Fig. 9, said valve is provided with a stem, 1, the latter protruding from casing, C. Said protruding part of valve stem, t, has a gear pinion, l,

with which meshes a rack, m, the latter be ing connected to a bell crank lever, 1111.", to

one arm of which is pivoted a link, in. the. latter being in turn connected to a slidablo collar, m". It will be understood that when collar, m, is moved in one direction, bell c 'ank lever, m and rack, m, are operated to turn the pinion and said valve, L, to different positions, whereby the valve may be adjusted to control the how of. liquid from the pump to themotor, or said valve may be operated to shut otl'circulation of the liquid through the motors and establish the flow of liquid through the by-pas's, y.

The piston, ll, of the reserve or idle motor, H, is shown in Figs. 1 and 9 as mounted loosely on the driven shaft, B, and as this motor is controllable manually so as to' bc brought inloservice under cerlaln con- I ditions in the operation of the. transmis ion mechanism, such as when driving the vehicle in a'bac-kward direction, suitable means must be provided for making the piston, H, of said reserve. motor fast. with the driven shaftfOne means form-complishing this result consists "in. the employment of a clutch nieclmni sm, herein shown in the form of a'sleeve, l which is spliued by a feather,

i, onsaid shaft, 13. The piston, 11. is chambered and'provuled in said chambered portion with a clutch face, i, \'vith which is adapted to engage aclutch face, 1', on .the

inner end portion'of the clutch sleeve, I.

" It" is evident that by sliding the clutch sleeve in an inward direction the face, 2', of said sleeve is adapted to cngage'cwith'the face,

F, of the motor piston, ll, thereby making said piston fast with the shaft, B. The clutch sleeve s adapted to be operated by suitable means, and in Fig. 9v of the drawings I have shown one embodiment of means adapted for operation. by the collar, or, so+13o that when the valve, L, is opened to admit the motive fluid to the chamber 6, of'the reserve motor the clutch sleeve, I, will be operated simultaneously to make the motor piston, H, fast with the driven shaft, B. A yoke, I is movable with clutch sleeve,I,

and this yoke, I is provided with arms, 5,

1, whereby valve, L, may be whereby said clutch sleeve is which are in the path of-the slidable collar, 112., said arms, 2' of the yokebeingprovided with coiled springs, i the latter being in the path of said collar, m

The casing, C, is shown in Figs. 1 and 9 as being cylindrical.. The housing, C, is of ss diameterthan the casing, and it is provided with slots, 2', through which pass the end portions of the yoke, I Said housing, 0', serves as a support, also, for the sliding collars, J and m The yoke, I isshown pressed normally in one 1*, which are seated'against the end of head of the casing, O, and these springs, I, tend to force yoke, I, and sleeve, I, in an outin Fig. 9 as being Ward direction for disengaging clutch face,. i of the sleeve from the iston, H, whereby the latter is adapted to e uncoupled from driven -shaft, B, and to remain idle with re{ spect thereto.

The means for ma latingvalve, L, insuchma'nner that when said valve, L, opens the motor chamber, 6,

for the admission of liquid to motor, H,

the clutch devices are immediately thereafter, or simultaneously therewith, operated to clutch the piston, H, fastto the driven shaft or member, B. Now, it will be re.- called that valve, L, is operated by movement of the collar, m, toward casing, C, so that a certain travel of 'saidcollar will take place without the collar, m, engaging with springs, it, or the arms, i, of the yoke,

certain distance to open motor chambers,

ther rotatevalve, L, and openph of reserve motor, H,.brings colla' engagement with springs,- i comp them, and operating theyoke I, said yoke being thus caused to actuate pi 11 d ged h "a fi 'i war y an enga wlt' pm 11 or making the latter'fast withjjshaft, 'B: It will thus be seen valve,- L, opens the motor chamber, .6, and wheifi fsgidvalve, L, is turned in an opposite direction for closing said chamber,'b, the' withdrawafof collar,

m, from springs, i,'.;= permits "springs, I, to act in moving s1eeve,-'I',ifin"an' outward provided at its righthand end portion with a housing, C, said housing being direction by springs,

. tions,

.as to impair the eificiency, ative, the transmission meehanism,-I employ means whereby the case, 0, may be coupled fast the motorrigidly .to the piston, H, with thedriven'shaft are'oper-" ated by the means for adjusting the reguE' B rotated for a sleeve,

Jtothe drivin a, a, without affecting the yoke, I". Afur ther movement of collar, m, sufiicient to .fur-

ith aggrooved collar, '7', I

reception-of -a suitable operating lever i'i'isa and each sleeve is, fur-'5 t h e e that'isl'eeve, I, operates-to clutch piston, H, to. thejdriven shaft 'im-' mediately aft-er The piston, H, of the reserve motor is provided. with a gear element, It, which loosely surrounds the clutch sleeve, I, and with this gear element, 725, meshes a gear k, that is fast with the abutment, H o the reserve motor, H, whereby said abutment, H is rotated in unison with the piston, H', of the reserve motor when the latter is brought into operation by the addirection, thereby disconiiecting piston, H, from shaft, B.

ju'stment of the clutch, I, and the final openmg movement given to the. member, p, of the controlling valve, L. 7

From the foregoing description it will be recalled that the -case,.(), is.loose or idle.

driving and driven shafts, A, respectively, whereby an automobile is enabled to return to its starting place, or continue on its journey, under its own motive power. In one embodiment of this part of the invention, case, 0, is adapted to be coupled to shafts, A, B, by clutches, "K, K, shown in Fig. 1 of the drawings. As shown Fig. 1, the clutches are of the k, which i'sfeathered shaft, B, the feather, '5, whereasthe shaft by afeather, i. The

sleeve of eac clutch, K, K,

well known manner,

b the clutch, K, is connected eve of the is provided adapted for the g thermore, providedwith a plurality of rods,

7", which carry; a plurality of disks, In, the .latter alternating with other 7:, whichare'threaded on rods, j, said 'rodsbeing, fastened to. an end of the case, 0.

It is evident that the collars, j, of the clutches,j,K,.K -.,amay beoperated in order thatthe disks,*k, k, of said clutches may be brol g U clutchesfo rate to make the with the and driventhus throwing outjof D, andthe motors; G, H.

Inconnedaon-withthe htEinto engagement, 'whereby the' case, 0, fast 7 shafts, A, "B,.' operation the pump,"

multiple disk type, and each clutch is Y provided witha sleeve, -or splinedonthe shaft, the, 'clu'tch, 'K, being connected. the driven anism I contemplate the provision of means is adapted to serve as. a brake by the employment of means for holding the rotatable case, C, at rest and allowing the driven shaft, B, to. rotate freely when the vehicle is going down grade, and under these conditions the fluid is adapted to be forced by the motor or motors back to the pump, D, the piston of which .pumpand the shaft, A,

. are free to rotate, the power of the engine being shut off whereby the fluid is adapted to circulate through the casing, C. The means shown in Fig. 1 of the drawings for converting the transmission mechanism into a. variable power fluid brake is a suitablebrake, L, supported'on a stationary element of an automobile, such as the frame indicated at p. Said brake may be similar to the well known multiple disk clutch, which is shown as having rods, p fixed to an element, C of the casing, C, and on these rodsare the disks, 39 which alternate with other disks, 20 the latter being supported on rods, 79, which are fastened to the frame member, 22 see Fig. 1. 'A simple form of brake is' shown in Fig. 16 as consisting of a hand brake, if, adapted to embrace. a member, C of the casing, C. Said band brake, V, of Fig. 1G is intended to be mounted on a part of the machine frame,

and it. is adapted to be operated by the hand or foot .ofthe chauffeur, whereby either formof brake can be tightenedfor the purpose of locking the casing, C, in a stationary position. It will be understood that when the shaft, B, is rotated by the motion of the vehicle when descending a.

grade, and when the brake, L or W, is operated to clamp the casing, C, in a stationary position withrespect to the frame, the motor pistons, G, H, will rotate with the shaft, B. and force the fluid through the closed liquid circuit and the pump, D,'

whereby the liquid is forced to rrculate in a way to'oppo-se the rotation of shaft, B.

'Thespeed of rotation of the motors and the speed of the circulation of the fluid is regulated by the adjustment of the governing valve, L. thus opposing variable resistance to the rotation of the shaft, B, whereby the automobile is placed under control of the chauffeur when coasting. It is evident that the power of theengine should, under these conditions of service, be shut off, but the engine may run idly.

The transmission mechanism shown mainly in Figs. 1 and 9, contemplates the employment of an idleor reserve motor which is mounted loosely on the driven shaft, B, and

i's'adapted to be made fast therewith by the. i

operation of a clutch, such as I; but such clutch is thrown into and out of engage-- ment with the motor piston by devices intended to be operated by the hand or foot of the chauffeur. I consider it preferable, however, to employ means adapted for actu ation by the circulating'motive fluid in order to automatically couple the piston of said idle or reserve motor to the shaft, B, on the admission of the motive fluid to said motor.

a chamber, around the shaft, B, and with this chamber communicates a radial chamber, g, the latter opening outwardly through the periphery of said piston, H. In said chamber, 9, is a double acting clutch, Q, shown in the form of a pawl provided with teeth at its respective ends, and in the shaft, B, is formed an annular series of radial pockets, g adapted to serve the purpose of teeth with which the teeth of the double acting clutch are adapted to engage according. to the position of sald clutch. The clutch is represented as being mounted movably in the chamber, g, by a pivot, Q3, and said clutch is provided, also, with a radial member, 9*, which extends through the radial chamber, q. The outer portion of this member is enlarged to form a piston, 9 which is arranged to'work or travel in the chamber, 6, of the reserve motor, whereby said piston is exposed to the pressure of the motive fluid so that it will hold the clutch in one position or the other according to the direction in which the. fluid is caused to circulate through the chamber, 72. 7

Suitable means are employed for holding the radial member, qt, in a'position wherein the clutch will be idle and free from enoutwardly gagement with the shaft, B, said means being shown in Fig. 10 as coiled springs, 1, 9 arranged to engage with the respective sides of the member; said springs being seated in suitable pockets of the motor "piston, H. The abutment, H which cooperates with the motor piston, H, is provided with pockets, h adapted to accommodate the piston, g so as to provide for the clearance of said abutment, H by the piston. It .will be understood that when the fluid is admitted in a direction to drive the piston, H, in the direction indicated by the arrow in Fig. 10, the fluid will act on the wings of said piston, H, and on the piston, 9 of the clutch, thereby compressing the spring and throwing one prong as to couple the clutch automatically with "prong of the clutch, Q, into engagement with one notch of the shaft, B, whereby the clutch o eratesto couple the piston, H, with the shaf t, B. It is to be understood, therefore,.5"that"the+ clutch acts automatically in one direction or the other to make the piston, H, fast with the shaft, B, irrespective of the direction of the circulation of the motive fluid through the chamber, 6, of the reserve motor.

The principle of my invention is available, also, in the differential gear of automobiles,

. and in connection with the jack shaft of a chain driven car. In Figs. 1 2 and 13 there are shown, different embodiments of a differential gear contemplated by said invention. The divided rear axle of an automobile is indicated at R, R, and as having the usual driving wheels, r, and on said axleslare the motors, S, S, adapted to be driven from a pump of which pump is driven in any suitable way. The pump is connected operativelywith the respective motors by a suitable systemof piplng, and provision is made-for reversing the direction of the circulation of the fluid from the pump through the motors and back to said pump, the piping system and the reversing devices being shown diagrammatically in Fig. 12. Said pump, T, is provided with a plurality of pump chambers, t, in which operate the pistons, and from one side of the pump cylinderor casing extends, a feed pipe, t having a plurality of branches which are connected individually with the respective pump chambers. Said feed pipe, t has a cross ipe, t, which -is connected by a plura ity of branches, t ,.with the chambers of the mo-' tors, S, S, and inthis cross pipe, 25 are provided reversing valves, 23*, t which are connected operatively by a rod, 2?, adapted to be operated by a lever, It. A return pipe,

8, extendsfrom the motors back to the pump,

with which pump said pipe, s, is connected by a plurality of branches similar to the pipe, t

The feed ipe, t and the return pipe, 8, are connecte also, by a cross pipe,-s,' having a plurality of branches, 8, which are connected with the chambers of the motors in a similar manner to the connection between the cross pipe, f, by the branches,

and in this cross plpe, a, are reversing valves, 8 a, which are connected by a cross rod, 8, adapted to be movedlengt-hwise in either direction by a lever, S

When driving in a forward direction the valves are adjusted to the position shown in Fig. 12, and the pump operates to force the i T, the piston shaft t,

: fluid through the pipes, t t 25 into the motors, S, S, thereby rotating the latter and the axles. The exhaust from the ,motors is returned by the pipes, 8 s, 8, back to the pump. To reverse, the levers B S", are operated'in any suitable or convenient way in order to shift the valves, 25*, F, in the pipe, i and the valves, 8 s, in the pipe, 8, whereby the fluid passes through the pipes, t .5", and .3 into the motors in an opposite direction to that first described, the exhaust from said motors being through the pipes, t t and 5, back to the pump.

An element of the differential gear consists of one or a plurality of reducing valves, R adapted to regulate the circulating fluid for reducing the quantity admitted to one motor while permitting the other motor to receive the full load, whereby one motor and one axle can be driven with more power than the other motor or axle.- This is 'espemotors, 8*, S", in connection with a variable power pump, T. Said pump is shownas having a plurality of concentric shafts, u, u, u ,.each of which is provided with a piston adapted to operate in one of the compartments, t, of said pump. Said shafts are provided with gears, u, a, a adapted to mesh separately or simultaneously with gears, U, U, 'on a drive shaft, U Said gears, U, U,-are on-a slidable sleeve, U adapted-to be operated by a lever, U whereby the'gear, U, may operate the'shaft, u by meshing with its gear, a. It is evident that the sleeve, U may be shifted lengthwise of the shaft, U, for the purpose of making the gear, U, mesh with both gears,- u", u, and thereby drive the shafts, 21 u, for operating twoof the pump pistons; but a further adjustment of the sleeve, U brings the gear, U, into mesh with the gear, u, so that the shaft, ,u," will be operated simultaneously with shafts, a, a whereby all of the pistons will be positively rotated. The pipe system and the reversing valves in the differential gear shown in Fig. 13 are somewhat similar to the corresponding parts shown in Fig. 12. The feed pipe, I), is connected by a plurality of branches with thepump chambers, and the, return pipe, 8, is connected in a similar manner with said pump chambers. Said feed and return pipes are connected bythe cross pipes, t, s, the

former being connected by pipes, 25 with the single cylinder motors, S, S, and the latter pipe, 8, being connected with said motors by the pipes, 8 In the pipe, t", are reversing valves, t t adapted to be op system of Fig. 13 for the purpose specified in connection with the system of Fig. 12.

' In Figs. 14 and 15 of the drawings I have shown diagrammatically, for the sake of clearness of illustration, the operation of the pump and the motors in connection with the loosely mounted rotatable casing which is provided with the passages forming. a liquid circuit between the pump and said motors. The advantage secured by said roaxis with respect to shafts, A, B, said abut-f tatable casing is, mainly, that the frictional contact of the moving column of liquid, with the walls of the passages in the casing, is reduced to a minimum, whereby I am able to utilize to the best advantage the energy of theliquid. i

For propelling driven member, B, in the same direction as driving member, A, re-

. versing valve, J, is opened, as shown in Fig.

14, for the l1qu1d to flow through the pas-' sage, j, whereby liquid is supplied to the motor chambers, a, a, or a, a. and b, in a direction to drive the pistons of motor, G, or motors, G, H, in the same direction as the-pump piston, see the arrows in Figala.

Now, the moving liquid column impelled by the pump which is operated directly by the engine, the latter running usually at high speed, results in a certain amount of friction between said liquid column and the inner surfaces of the passages and chambers of the casing, C, and, further, the pressure of the moving liquid column against the abutments, E, Gr or E, G H causes the entire casing, C, to rotate on its longitudinal in'ents, E, G and H (which are mounted in said casing) rotating therewith. The direc-- non of rotation of the casing depends upon various conditions, but with valve, J, ailjusted to direct the flow of liquidiu the direction .shown ,in Fig. 14, the casing, C, rotates freely with respect to both shafts, A, B.

The automatic brake mechanism, V, shown in Fig. 17, or the manually operated brake mechanism, W, of Fig. 16, or the brake, L, of Fig. 1, may be operated, however, for the purpose of precluding the rotation of said casing, O, the brake, V, acting automatically to restrain the casing from backward rotation.

Fig. 15 of the drawings shows the mechanism diagrammatically for driving the motor or motors in an opposite direction .to.

that the valve, J, is adapted to be operated for changing the direction of flow of the liquid through the chambers, a, a and I), of the motors, G, H. When it is desired to drive the motor or motors in a reverse direction, to the, pump, D,'- as shownby the arrows in Fig. 15, valve, J, is adjusted to ,cause the liquid to enter the motor or motors through the passage, j, i, and to return to the pump by the passage, '5, j. The liquid is thus forced by the pump through the motor or motors in an opposite direction to that indicated in Fig. 14, whereby the pistons of the motors, G .and H, are driven in the direction indicated by the arrows in Fig. 15.

I The pressure of the liquidon theabutments, -E, G H of the pump and the motors, and

the frictional engagement of the moving liquid column with the nner surfaces of the casing, C, causes said casing, C, to rotate -with respect to the-pistons of said pump and motors and to shafts, A, B.

It will beunderstood that the abutment, E, of the pump, and the abutments, G H of the motors rotate with the casing, and thus the fluid forced by the pump may be said to drive the casing under certain conditions, and said casing in turn drives the motor or motors, the abutments, G H act- I ing as pistons in forcing the fluid through i the chambers, a, a, b, of the .motor or motors 5 for the purpose of driving the motor pistons which in turn drive the driven element.

Under some conditions of road service, particularly when the mechanism is adnsted on a reverse drive for propelling an automobile in a backward direction, and at slow speed but with the greatest power,

it is possible that the casing, C, for the working. parts of the mechanism may have a tendency to turn in an opposite direction to the motor piston. -Any suitable means may be employed for overcoming this back restraining the casing against backward rotation. Said arrangement of Fig. 17 contemplates the 1 employment -of dogs, 11, mounted on a stationary part, 30 of the frame in such a way that the casing is free torotate in the same direction as the pump piston, but when the casing has a tendency to turn backwardly the dogs will become wedged in position between said casing and the stationary frame element, 22 thereby locking the casing temporarily against backward movement. e

-' InFig. 16 of the drawings I haverepresented a simple embodiment of the invention wherein the driven element, B, is in the form of a sleeve fitted loosely on the driv- 13o ing shaft, A, adapted to extend through said sleeve. The piston of the pump, D, is attached directly to the driving giaft, A, and "the pistons of the motors, and H, are carried by'the driven element, B, in the form, of the sleeve, the piston of the motor, G, being fixed to the driven sleeve B, while the'piston of the motor, H, is adapted to be made. fast with said driven sleeve, B, in either of-the ways heretofore, described, or in any) equivalent manner. Provision is made for coupling the driving and driven elements, A, B, directly together, thereby dispensing with the multiple disk clutches,

- multiple diskbrake, L, shown in Fig. 1 op-' K, K, in the construction of Fig. 1. A slidable clutch, X, is splined on the driving shaft, A, for movement thereon when the shipper rod, X, is operated. The driven sleeve, B, is provided with a clutch face, :0, adapted to be engaged by the face of the clutch, X, whereby the driving and driven crates with the same advantage in connection with the fluid transmission mechanism.

as the brake, W, in the construction heretofore described and illustrated in ig. 16.

Having thus'fully described my invention, what I claim as new and desireto secure by Letters Patent is 1. In an apparatus of the class described, driying and-driven -members,"acasing pro videdwith a liquid circuit-,said casing being rota-table relative to said, members, meansufo-r locking the-casing against rotation in either direction, a motor operated by.

liquid adapted to circulate in said casing,

I and means for circulating. liquid in said casing.-

:2. In an apparatus of the class described,

vdriving and driven members, a casing rotatable relative to said members, means for restraining said caslng against'rotation m directions, a pump operable by the. driving member for circulating liquid in,

said casing, means operated by the circulating liquid in the casing for propelling the driven member, and additional means adapted'to also be operated by the circulating liq uld and' cooperating withsaid driven memher, said additionalmeans supplementing the actionof the first named liquid driven for unitary rota-tion.

means and cooperating therewith to exert increased torque on the driven'member.

3. A hydraulic transmission mechanism comprising a single rotatable casing, means for restraining said casing from rotation in either direction, drivlng and drlven mem- V bers, a pump within the casing and operated by the driving member for circulating liquid through the casing, a plurality of motors within the casing and adapted to cooperate with the driven member, said motors .being adapted for operation by the liquid circulating in the casing, and means operable at will for admitting the liquid to one of the motors to the exclusion of the other motor and for admitting liquid simultaneously to both motors.

4. In an apparatus oftheiclass described, v

driving and driven members in alinement with each other, a'liquid circuit, a liquida driving member, liquid pumping mechanism operated thereby, a motor operated by the liquid from said pumping mechanism, a driven member operated by said n otor, a casing-rotatable relative to SillddllV- ing and driven {-inembers, means for controlling the rotation of said casing, and means for cqupling the driving and driven members for rotation as a unit.

6. In an apparatus of the class described, driving and driven members, acasing rotatable rel'ativejto said members, means operated by the driving member for circulating liquid through said casing, a motor cooperating with the }driven member and adaptedto. be operated by the circulating liquid, means for checking the rotation of 'said casing in both directions, and means for coupling the driving anddriven members -7. In a liquid" transmission mechanism,

driving and driven members,a casing rotatable relative to said members, said casing having a liquid circuit, means operated by the driving member for forcing .liquid through'the circuit, thereby rotating said casing, a plurality of motors within the I casing and operable by the liquid circulating therein, and means whereby one of said motors may be coupled to, or uncoupled from,

said driven member.

8. In an apparatus of the class. described, driving and driven members, a rotatable casing provided with "a liquid circuit, means 95 5. In an apparatus of the class described, a 

